1. Field
Exemplary embodiments of the present disclosure relate to recovery of nickel from industrial pickling acid solutions.
2. Discussion
Water pollutants poison drinking water, food, and/or animals through buildup of environmental toxins in animal tissues, upsets the biological diversity of river and lake ecosystems, causes acid rain deforestation, and lots of other problems. Most of these problems are contaminant specific. Among water pollutants, the most notorious kinds of pollutants are metals. Many metals such as nickel, mercury, lead, cadmium and tin are highly toxic in minute concentrations. As metals are highly persistent, they can accumulate in food webs and have a cumulative effect in top predators including humans.
Although, nickel appears to be of lower toxicity in humans, there is some evidence that inhaled nickel may be carcinogenic. Nickel enters in soil and water from the wastewater generated in electroplating, metallurgical operations, rinse water from different industrial operations, etc. During the metallurgic extraction of nickel, pickling acid solutions are used which contain high concentration of nickel and need immediate attention. The large amount of nickel in waste pickling acid solution goes to waste. During the extraction process, about 100 g/l nickel is wasted and millions of dollars are spent for disposing it of properly. By using the process reported in the instant invention, substantial savings could be generated from the recovery of nickel as well reduced cost of its disposition.
The removal of metals from water is the most important need of the day because it can reduce the cost of metal recovery, reduce water pollution and thus reduce the health hazards of pollution with metals, which may include diseases like cancer, metal toxicity, kidney disorders, etc. Different methods for the nickel recovery and removal have been reported.